Hello,
I have everything to build a rig, mobo, sever case, cpu, ram. The only expense is the graphics cards. I planning to buy 5x Nvidia GTX 1070s because the GTX 1080 does not come out well in price/performance comparison.
I could get a GTX 1070 from wholesaler for about 320Eur new with 3 years of warranty (which certainly will be needed if the cards are running 24/7 mining coins) so with the pcie extending cables we talking about a ~ 1700 Eur investment.
I have the money to buy these already but here comes the fun part I want to build this rig 4 FREE because as we all know “the best things in life are free” 
So my idea would be to buy a certain amount of ZC/Bitcoin/Etherum etc. wait until they go up in price to a point where I make a profit to buy the cards and then sell it.
Would Zcash be able to go up that much in the next 2 month to make my investment worthy already? About bitcoin I doubt that it will fall back under 1K and it is just too risky to buy now.
For those who are experienced buyer/sellers here: which are the current exchanges where it’s worth to do it (no hidden fees, no fraud)?
Would it be worth buying bitcoins on https://www.bitstamp.net/ and then convert them to Zcash?